1. Field of the Invention
The present invention relates to a head slider to be incorporated in a recording medium drive or storage device such as a hard disk drive (HDD), for example. In particular, the invention relates to a head slider including: a slider body defining a medium-opposed or bottom base surface; a front support protrusion standing on the slider body near the leading end of the slider body; and a rear support protrusion standing on the slider body rearward of the front support protrusion near the trailing end of the slider body. The tip ends of the front and rear support protrusions are located above the level of an air bearing surface defined on the slider body.
2. Description of the Prior Art
A so-called contact start stop (CSS) control is well known in the technical field of a hard disk drive (HDD). A head slider in general employed in the HDD utilizing the CSS control is often provided with front and rear support protrusions standing on the medium-opposed base surface of the slider body, as disclosed in Japanese Patent Application Publication 10-302238. The front and rear support protrusions serve to reduce the adsorption or meniscus effect between the slider body and a lubricant film spreading over the surface of the magnetic recording disk when the slider body is seated on the still magnetic recording disk. This leads to establishment of a reliable CSS control.
A magnetoresistive film is often utilized to read magnetic information out of the magnetic recording disk in HDDs. If the magnetoresistive film collides against a contamination located on the surface of the rotating magnetic recording disk, for example, the signal from the magnetoresistive film should suffer from a so-called thermal asperity. The thermal asperity leads to an error in reading the magnetic information, as conventionally known.
The rear support protrusion is utilized to prevent the thermal asperity in the above-referenced head slider. The rear support protrusion is expected to collide against a contamination in front of the magnetoresistive film during rotation of the magnetic recording disk. The magnetoresistive film can be prevented from colliding against the contamination behind the rear support protrusion. The magnetoresistive film is mostly protected from the collision in this manner. The thermal asperity can be prevented.
The rear support protrusion is preferably located closer to the magnetoresistive film in the above-referenced head slider, in order to reliably prevent the thermal asperity. The closer to the magnetoresistive film the rear support protrusion is located, the fewer collisions take place between the magnetoresistive film and the contamination. However, if the rear support protrusion gets closer to the trailing end of the slider body in this manner, the magnetoresistive film cannot sufficiently approach the magnetic recording disk. Improvement in recordation density should be hindered. In this case, if the height of the rear support protrusion is reduced, the magnetoresistive film is allowed to further approach the magnetic recording disk. This smaller rear support protrusion leads to increase in the adsorption of the lubricant film acting on the head slider. A larger adsorption leads to obstruction to the commencement of the rotation of the magnetic recording disk.